A US flag flies over the entrance to the Federal Reserve Bank of New York on July 29, 2011. A Bangladeshi native was arrested Oct. 17, 2012, in an alleged plot to blow up the building, authorities say.

Quazi Mohammad Rezwanul Ahsan Nafis had only been in the US for nine months when he was arrested by federal authorities on Wednesday.

Nafis, with the help of an undercover FBI agent posing as an "Al Qaeda facilitator," had allegedly packed a van full of what he thought were explosives this week, NBC reported. After parking the van in front of the Federal Reserve building and walking to a nearby hotel, Nafis attempted to detonate the vehicle remotely with a cellphone, according to The New York Times, citing the complaint against him.

The Times wrote:

"...The entire plot played out under the surveillance of the Federal Bureau of Investigation and the New York Police Department as part of an elaborate sting operation, according to court papers.... The case appears to be the latest to fit a model in which, in the process of flushing out people they believe present a risk of terrorism, federal law enforcement officials have played the role of enabler."

The native of Bangladesh, 21, was arrested and charged with trying to blow up New York's Federal Reserve Bank with what he believed to be a 1,000-pound bomb. He also stands accused of supplying material support to Al Qaeda.

While it's impossible to speculate on the guilt, innocence or intent of the accused, the case nonetheless — as the Times points out — brings up the thorny question of where to draw the line between fighting terror and provoking it.

"Since 9/11, the FBI has undertaken the most significant transformation in its history," the Justice Department wrote in 2008. Changes have also taken place at the local criminal justice level.

Observers and opponents have long noted the cost of those transformations to the freedoms and privacies of individuals inside the United States, both in terms of surveillance used against individuals, and in how interference by authorities could possibly enable people who might not have acted on their own.

Nafis's father, Quazi Mohammad Ahsanullah, contended on Thursday his son was not just enabled by authorities, but set up, declaring his son the victim of a "racist conspiracy," according to Reuters. "He fell into a trap," Ansanullah said.

Is the US striking the right balance between security and personal freedoms?

The question isn't new, but the answer remains elusive.

"Civil liberties have taken a backseat to preempting terrorism, there’s just no doubt about it,” Columbia University foreign policy and counterterrorism expert Stuart Gottlieb told GlobalPost.

“And that’s because, whether you were under the Bush or the Obama administration, they still are operating under the premise that there are groups and individuals trying to do some pretty bad things, and they need to have the policies in place that remain controversial with civil libertarians … that will preempt attacks, rather than just respond to them after they occur with the criminal justice system.”

Brennan said it's been a priority of the Obama adminstration to counter terror within "the limits of the law," while respecting civil liberties. "Rather than security, vigilance is what we want," Brennan told Woodruff.

"It doesn't mean that you spy on your neighbors," but it is the reason for the "see something, say something" campaigns by the Department of Homeland Security, he continued.

Brennan contended that the US, as of 2011, was "without a doubt" safer than before 9/11. Among the reasons for that new safety are "the better integration of intelligence and law enforcement and homeland security capabilities over the last decade," he said.

But it's that integration, in large part, that has raised many of the concerns over domestic civil liberties.

"The Foreign Intelligence Surveillance Act (FISA) provides a statutory framework by which government agencies may, when gathering foreign intelligence investigation, obtain authorization to conduct electronic surveillance or physical searches, utilize pen registers and trap and trace devices, or access specified business records and other tangible things....

"Shortly after the 9/11 terrorist attacks, Congress enacted the USA PATRIOT Act, in part, to “provid[e] enhanced investigative tools” to “assist in the prevention of future terrorist activities and the preliminary acts and crimes which further such activities.”6 That act and subsequent measures7 amended FISA to enable the government to obtain information in a greater number of circumstances. The expanded authorities prompted concerns regarding the appropriate balance between national security interests and civil liberties. Perhaps in response to such concerns, Congress established sunset provisions which apply to three of the most controversial amendments to FISA."

The provisions were extended in 2011 until June, 2015, delaying the "sunset" of the controversial measures.

“Something like the uncovering of the plot in lower Manhattan the other day, that has to come from very strong Patriot Act-type provisions and probably beyond Patriot Act — so we’re talking about a whole variety of surveillance techniques that are aggressive and preemptive that are obviously operating pretty effectively," Gottlieb, the counterterrorism expert, said.

“For every plot you see disrupted, there are hundreds and hundreds of leads all over the place that are using aggressive intelligence and surveillance methods,” at the city level in New York and nationally, he continued.

“This is one individual who was discovered, but the question is, how many more individuals are being tracked, and how many of them are involved with terrorism in any way, and how many of them aren’t? And, what does that say about their civil liberties?”

Where do you think the line between counterterrorism and personal freedoms should fall? Let us know in the comments below.